The self-consistent-field density-functional-theory (SCF-DFT) calculations were performed in terms of the four-component Dirac electronic Hamiltonian [1]}, [2]}, which includes relativistic effects non-perturbatively. For its Green function solution, we have resorted to the SPRKKR package [3]}. Adoption of the local spin density approximation (LSDA) exchange-correlation functional by Vosko, Wilk and Nusair [4]} and of the atomic sphere approximation have been previously found adequate to reproduce CuMnAs experimental trends for ground state magnetism, Néel transition temperature, and charge transport [5]}, [6]}, already at the linearized muffin-tin orbitals (LMTO) level [7]}. These approximations have also shown a good agreement with ab initio results produced by very different computational frameworks such as the plane wave basis set and the pseudopotential scheme implemented within the Vienna ab-initio simulation package (VASP) [8]}, as well as the fully relativistic linear combination of atomic orbitals (LCAO) scheme by the full-potential local orbital (FPLO) package [9]}. We use experimental lattice parameters from thin film X-ray diffraction measurements [10]}
and include an additional \(2c\)  Wyckoff position for two supplementary empty sphere sublattices, to improve convergence of the multiple scattering expansion.
